A navigation apparatus disclosed, for instance, in Patent Literature 1 displays an image of a direction sign that indicates directions to possible destinations of respective roads connected at an intersection. When the distance between a host vehicle and an intersection toward which the host vehicle travels is equal to or shorter than a predetermined threshold value, the navigation apparatus disclosed in Patent Literature 1 controls a display screen to display the image of a direction sign indicating direction information at the intersection. This configuration enables a driver to recognize the direction of intended route at the intersection by viewing the direction sign.
Meanwhile, a navigation apparatus disclosed in Patent Literature 2 displays a facility mark, which serves as a landmark, over an enlarged view of a target intersection when the distance between the target intersection and a host vehicle is equal to or shorter than a predetermined value (enlarged-view display distance) during route guidance. Here, the target intersection is, for example, an intersection at which a left turn or a right turn is required to be made under route guidance or an intersection having a complicated shape.
Using the navigation apparatus disclosed in Patent Literature 1, the driver can check an image of a direction sign, which is installed at an intersection for guidance purposes, and is able to recognize the direction of intended route (for example, moving straight forward or turning left) at the intersection. However, the image of the direction sign does not include information about a facility serving as a landmark of the intersection. Therefore, for example, when another intersection exists near the intersection associated with a currently displayed direction sign image, the driver may erroneously recognize another intersection as the intersection associated with the currently displayed direction sign image. When such erroneous recognition occurs during a display of the direction sign image for the target intersection, the host vehicle deviates from the guidance route.
When the navigation apparatus disclosed in Patent Literature 2 is used to display an enlarged view of an intersection, the information about a facility serving as a landmark of the intersection is displayed together with the intersection. This reduces the possibility of the driver missing a target intersection. However, Patent Literature 2 does not describe a scheme for displaying a direction sign image. Besides, Patent Literature 2 does not describe a display condition of a direction sign at an intersection and a display condition of an enlarged view of an intersection.
Further, Patent Literature 1 describes the display of a direction sign image, but describes nothing about display of an enlarged view of an intersection. Further, Patent Literature 1 also does not describe a display condition of a direction sign at an intersection and a display condition of an enlarged view of an intersection. In other words, a method of switching between the display of a direction sign image at an intersection and the display of an enlarged view of the same intersection has not yet been studied.